286 FUNGUS-FLORA. 



Geotrichum candidum. Link. (fig. 17, p. 313.) 

 Tufts pulvinate, ■white, rather powdery ; sterile hyphae 



creeping, somewhat continuous ; fertile ascending, short ; 



conidia cylindrical, truncate at both ends, 5-10 x 4, hyaline. 

 Geotrichum candidum. Link, Obs., i. p. 15; Sacc, Syll., 



n. 183. 



On the naked ground, also on damp, rotten paper, 



bones, &c. 



Geotricliuni roseum. Grove. 



Hyphae creeping, white, interwoven ; conidia pale rose- ' 

 coloured, concatenate, shortly cylindrical, ends truncate, 

 16-30 X 9-10 fji. or sometimes longer. 



Geotrichum roseum, Grove, Journ. Bot., tab. 266, f. 8 ; 

 Sacc, Syll., iv. n. 185. 



Forming dense small, round or oblong rosy spots at the 

 base of a species of Juncus. 



OIDIUM. Link (emended), (fig. 8, p. 313.) 



Growing on living plants. Mycelinm creeping, conidio- 

 phores erect, sub-simple ; chains of conidia soon breaking 

 up ; conidia rather large, elliptical, colourless or coloured. 



Oidium, Link, emended by Saocardo, Mich., ii. p. 15; 

 Sacc, Syll., 40. 



Developing on living plants, chiefly on the leaves. Many 

 species have been proved to be the conidial condition of 

 ascigerous fungi belonging to the Ferisporiaceae. 



I. On Dicotyledons. 



Oidium erysiphoides. Fx. 



Broadly effased, indeterminate, white ; tufts conspicnons, 

 rosy- white ; hyphae almost erect, very slender ; conidia 

 ovate, oblong, pellucid, internally grannla.r, 30-45 X 13-20 fi. 



Oidium erysiphoides, Fries, Syst. MycoL, iii. p. 432 ; Sacc, 

 Syll., iv. n. 189. 



On living leaves of various plants. The conidial phase of 

 a species of Erysiphe. 



Oidium leucoconium. Desm. (fig, 8, p. 313.) 

 Tufts broadly effused, white ; hyphae creeping with short, 

 erect, fertile branchlets ; conidia elliptical, 20-30 x 13-16 //,. 



